Improvement in receivers for electro-harmonic telegr-aphs



E. GRAY. 4 Receiver for Electro-Harmunic Telegraph.

No. 166,094. Patentedlulyzmlms.

j'ig z WITNESSES Elzlvfla 'zwy 11v VENTOR By 7;?13 Attorney UN TED STATES PATENT OFFICE.

ELISHA GRAY, 0Fv CHICAGO, ILLINOIS.

IMPROVEMENT. m RECEIVERS roR ELECTRQ-HARMONIC 'TELEGR'APHS.

Specification forming part'of Letters Patent Iii-1. 615,094, dated July 27,1875; application filed June 28.1875.

To all whom itmagjconcern: e

Be it knownth'at'l, ELISHA' GRAY, oi. Ohi cago, in the cou'nty of (look andState of Illinois, havein'vented a certain new'and useful Improvement in Receivers for. Electro-Harmonic Telegraphs, of which the following is a I specification In apreyious appli" I tion for Letters Patent of the United'fitates, filed February 23, 1875,

for apparatus for transmitting musicalvibra' tions byelectricity, I have shown and'described an instrument for receiving musical tones, called an analyzer, composed of a seeries of vibratinginstruments, each tuned to a different pitch,-which receives from the transmitter those tonesonly which correspond to its own fundamental vibrations when exeouted. by mechanical means. I have also shown in said application a method of making andv breaking a loeal'circuit, so as to record Morse or other signals in the ordinary way, the analyzer taking the place of the common Morse relay, the inter brations or signals being made at the-sending end'by a'common telegraphic key, The circuit-interrupter,described in my previous'apvplieatlon above mentioned consisted of a light Ifnetal spring or lever fastened at one end to a'post, while its free end rested upon the analyzing-springer vibrating reed, the contact point between the two being made of platinuni, and the lever having a rate of vibration slower than that of the analyzing-springer reed, which is' actuated by electrical impulses from the transmitting end otitheline, which synchronize with the natural or fundamental vibration of the analyzing-spring at the receiving end, the tension or rate of vibration of the lever being made adjustable to a certain extent b'y'a screw provided'for that pur-,

options in. the vi-- ing point on the vibrating bars.

the analyzing-spring, but is made to jiar or rattle at the point of contact, andlforall practical purposes it opens the" local circuit, and holds it open so long as the analyzing-spring continues to vibrate. When the vibration ceases, the points-come to rest, and the circuit is reestablished, operating a magnet in 'the ordinary way.

My present invention constitutes an improvement upon the receiver shown in the application above-mentioned, and consists in an vimproved device for operating the local circuit.

in the accompanying drawings, which' rep resent so much of my improved receiving apparatus as is necessary to illustrate the st ject-matter herein claimed, Figure 1 is a plan or top view Fig. 2, a vertical transverse sectim therethrough on the line :1 00 of Fig. 1

The battery-wires are connected with binding posts or screws B B G G, mounted, as usual, upon a base-board, A. The receiving apparatus is mounted upon a triangular frame, D, of metal, suitably secured to this base by screws or other well-known means. An ordinary electromagnet, E, is mounted upon this frame, with its poles at right angles to, butin the same horizonta plane as, the vibrating tension-bar or analyzing-spring F, provided with suitable tension devices-for regulating the pitch of the tone produced by its vibrations. A light metal elbow-lever or circuitinterrupter, G, rocks on pivots g in an insu lated post, H, mounted on, the metal frame D.

The freeend of this lever is provided with a I platina contact-point, resting on a correspondlever is designed to vibrate at a slower rate than-the analyzer-spring. This rate of vibration is regulated by a small spiral spring, i, one endof which is attached to the elbowlever, and the other is connected by a cord to a Windlass or pins, 1, turning in hearings in the post H. The main current enters the magnet through the wire M, and passesout through the wire M. The local current consists of the wires L L.

In operation, the impulses transmitted through the main line throw the receiver or "analyzing-spring into vibration, and as the The elbow-' elbow -lev er G vibrates more slowly, the cirf0! fl( 1jll 8fil1g thfl rate of vibration of said cuit; is praotiuallykept open until closed-by lever. 5 1

the key, ns lwrciubefore explained. Iu testimony ii hereof I-have'hcreunto Silh- I claimscribed ,mynmne. The combination, substantially as heiein- V ELISHA- GRAY. before set forth, of the vibrating receiving Witnesses spring, the elbow-lever circuit-interiup'fir,and I WM. J. PEYTON,

mechanism, substantially'such as described, E. O. DAVIDSON; 

